Microscopes, image projectors, industrial laser optical systems, and various other optical systems have been used to control the sizes of images at a target location. Many such optical systems employ lenses and/or mirrors which are translated relative to each other along the optical axis of the system in order to control the output image size. In some systems, changing the size of the image alters the location of the plane at which the image is in focus. Moreover, some conventional systems can be relatively bulky, and require complex mechanical components.
In the article “Optical System for Image Rotation and Magnification,” J. Opt. Soc. Am. 70(2), February 1980, Braunecker et al. describe an optical system including a pair of rotatable, adjacent cylindrical lenses having focal lengths of equal magnitude and opposite signs. Braunecker et al. further show an additional, non-adjacent spherical lens situated away from the pair of cylindrical lenses.